1. Field of the Invention
The present invention relates to application specific integrated circuits (ASICs), and more particularly, to using ASICs' in different platform/operating environments.
2. Background of the Invention
ASICs are commonly used in different applications and operating environments. For example, ASICs are used in host bus adapters (HBAs) and switch chassis/elements. HBAs and switches may be used in different operating environments, for example, Fibre Channel, InfiniBand and Serial Attached SCSI based networks.
Typically, ASICs for HBAs and switches receive and transmit data via a network connector located on printed circuit boards (PCB). To operate the ASIC, a positive data signal is fed to a positive input pin of the network connector and a negative data signal is fed to a negative input pin of the connector.
The network connector can be on the top or bottom side of the PCB. If the network connector is on the top side of the PCB, data signals are routed directly to the pins of the connector with minimal loss of signal integrity.
If the network connector is on the bottom side of the PCB, the ability to maintain signal integrity has challenges. For example, a signal trace has to change routing layers so that the ASIC can function and maintain integrity in different environments. To accomplish this, extra via structures may be placed on PCB traces. Via structures may be used so that data signals from the ASIC cross over to connect to the pins of the network connector. This approach has disadvantages because it causes degraded signal integrity, reduced propagation distance and increased jitter.
Another approach is to design a separate ASIC for each environment/platform. For example, separate ASICs (switch element or HBA) may be used in a Fibre Channel network, InfiniBand and Serial Attached SCSI based networks. This solution is expensive and hence is undesirable.
Therefore, there is a need for a method and system that allows an ASIC to be used in different environments/platforms without causing significant signal integrity degradation.